Endgame Databases
Chess endgame databases, while of important theoretical interest, have yet to make a significant impact in tournament chess. In the game of checkers, however, endgame databases have played a pivotal role in the success of our World Championship challenger program Chinook. Consequently, we are interested in building databases consisting of hundreds of billions of positions. Since database positions arise frequently in Chinook's search trees, the databases must be accessible in real-time. This does not yet happen in chess.
The following links show the number of positions in checkers:
- Total number of positions
- By number of black and white pieces
- By number of piece types
- By leading checker rank
Chinook has perfect information for all checker positions involving 8 or fewer pieces on the board, a total of 443,748,401,247 positions. These databases are now available for download! Note that some of the following files are large. The total download size is almost 2.7 GB. Unzipped size is 5.6 GB.
If you prefer CDs, please contact jonathan@cs.ualberta.ca (we have to charge a nominal fee to cover costs).
Download the databases:
- 2- through 6-piece db (ZIP)
- 7-piece db: 4 vs 3 with strong side having 0 kings (ZIP)
- 7-piece db: 4 vs 3 with strong side having 1 king (ZIP)
- 7-piece db: 4 vs 3 with strong side having 2 kings (ZIP)
- 7-piece db: 4 vs 3 with strong side having 3 kings (ZIP)
- 7-piece db: 4 vs 3 with strong side having 4 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 0 kings and the other 0 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 1 kings and the other 0 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 2 kings and the other 0 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 3 kings and the other 0 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 4 kings and the other 0 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 1 kings and the other 1 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 2 kings and the other 1 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 3 kings and the other 1 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 4 kings and the other 1 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 2 kings and the other 2 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 3 kings and the other 2 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 4 kings and the other 2 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 3 kings and the other 3 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 4 kings and the other 3 kings (ZIP)
- 8-piece db: 4 vs 4 with one side having 4 kings and the other 4 kings (ZIP)
Database access code. Note that this code isn't as "nice" as it should be.
